Whats the answers.............
1. m=1/2 b=4 y=1/2x+4
2. m=-1/2 b=-3 y=-1/2x-3
3. m=-3/2 b=-1 y=-3/2x-1
4. m=1/2 b=-1 y=1/2x-1
Answer:
a = 195 ; c = 615
Step-by-step explanation:
So, you want to start by forming your equations...
I will use 'c' for children and 'a' for adults for my variables
3a + 30 = c
(this is because of the info that 30 more tickets than 3 times the amount of children's were sold than adult)
then for equation 2:
3c + 5a = 2820
(this is because of the prices of the tickets and the total money raised)
Then, plug in the equation for c
Your equation should look like:
3(3a + 30) + 5a = 2820
You get:
(9a +90) + 5a = 2820
Then:
14a = 2730
So:
a = 195 adult tickets sold
Plug in a, to find c:
3 (195) + 30 = c
585 + 30 = c
c = 615 children tickets sold
Answer:
78.5
Step-by-step explanation:
Answer:
Step-by-step explanation:
Hello!
The objective is to compare if the average time that families live in Gotham and Metropolis, the real state company thinks the average time is less in Gotham than in Metropolis. There are two populations of interest and therefore two variables:
X₁: Time a family has lived in Gotham.
n₁= 100 families
X[bar]₁= 35 months
S₁= 900 days
X₂: Time a family has lived in Metropolis.
n₂= 150 families
X[bar]₂= 50 months
S₂= 1050 days
You are studying the population means of both variables, so you have to work using the distribution of the sample means:
If:
X[bar]₁~N(μ₁;σ₁²/n₁)
X[bar]₂~N(μ₂;σ₂²/n₂)
We can say that the difference between these both distributions will have the following distribution:
(X[bar]₁-X[bar]₂)~N(μ₁-μ₂;σ₁²/n₁+σ₂²/n₂)
The population variance for the difference between the two sample means is:
σ₁²/n₁+σ₂²/n₂
Since both σ₁² = σ₂² = σ² we can say that:
σ² (1/n₁+1/n₂)To study the difference between two normal populations with unknown bu equal population variances the distribution to use is:
The estimation of the standard error of the difference is:
Sa= 992.8423≅ 992.84
The standard error of the difference between the two sample means is 128.18.
I hope this helps!